Abstract: A process for continuously preparing a wet powder of PTFE, comprising the step of continuously slurrying a PTFE aqueous dispersion with a high shear machine, and the step of continuously granulating the slurry by using vertical agitator. The process can be carried out for a long time without trouble, and can continuously provide a dry powder having good powder properties. The powder properties can be controlled by regulating operation conditions.

Abstract: A process for recovering glycols produced during recycling of polyester comprising the step of extracting aromatic contaminants from the glycols. Extracting the aromatic contaminants is accomplished by: providing a glycol rich stream from a process to recycle polyester. The glycol rich stream comprised glycols, water, and aromatic contaminants. A solvent is added to the glycol rich stream to form a mixture. The mixture is resolved to form a glycol rich component and an aromatic contaminant rich component. The glycols are recovered from the glycol rich component.

Abstract: A process for purifying a polymer by separating and removing volatile components from a polymer composition containing the volatile components, which comprises: (a) heating the polymer composition containing a methanol solvent to a temperature of 120.degree. to 240.degree. C. by a heater, wherein an internal pressure the heater is maintained at 8 to 35 kg/cm.sup.2 G; (b) discharging the heated polymer composition into a tank in which pressure is maintained at -0.7 to 1.0 kg/cm.sup.2 G, and then separating and collecting most of the volatile components to lower the concentration of the solvent in the remaining volatile components in the polymer composition to 0.5% by weight or less; and (c) feeding the resultant polymer composition to a vent extruder maintained such that a barrel temperature at an inner side thereof is 160.degree. to 280.degree. C.

Abstract: The present invention is directed to a purified polyalkylsiloxane composition having a boiling point, under atmospheric conditions, of less than about 250.degree. C. and containing high boiling impurities, including siloxanes and silanol-terminated siloxanes, that have boiling points, under atmospheric conditions, of greater than about 250.degree. C. in a total concentration of less than 14 ppm. The present invention is further directed to a method of producing a purified polyalkylsiloxane composition, having a boiling point, under atmospheric conditions, of less than about 250.degree. C., by distilling a polyalkylsiloxane starting material containing high boiling impurities having boiling points, under atmospheric conditions, of greater than about 250.degree. C. in a total concentration of at least 14 ppm, under conditions effective to produce a purified polyalkylsiloxane composition having a boiling point under atmospheric conditions of less than about 250.degree. C.

Abstract: Aqueous dispersions of cationic water-soluble polymers are provided, as well as processes for making and methods of using the same.

Abstract: Shaped articles are obtained from a polymerization mixture of soluble wholly aromatic polyamides in a gel state.

Abstract: A novel process has been developed for the crystallization of poly(ethylenenaphthalenedicarboxylate) (PEN) and its copolymers. The process comprises the step of maintaining the amount of water in said poly(ethylenenaphthalenedicarboxylate) below a critical moisture content ceiling throughout processing such that a separate drying step is not required.

Abstract: A preparation process of solid polyhydroxycarboxylic acid comprising subjecting an organic solvent solution of polyhydroxycarboxylic acid to cooling.cndot.solidification and grinding. The preparation process can provide high molecular weight solid polyhydroxycarboxylic acid with ease and cheaply, can be converted with ease to a continuous system, and is useful in industry.

Abstract: The present invention discloses novolacs and thermosets thereof containing mesogenic moieties. Certain of said novolacs and thermosets thereof exhibit nonlinear optical properties upon orientation.

Abstract: In a process for producing a polycarbonate by subjecting a dihydroxy compound and a diester of carbonic acid to melt polycondensation through transesterification, after a polycarbonate prepolymer is prepared in the first-stage reaction, polycondensation is conducted as the second-stage reaction in a residence time in the range of from 15 to less than 60 min or through the use of at least one paddle-type self-cleaning twin-screw extruderThis process enables a colorless, transparent polycarbonate having a high molecular weight to be produced at a high efficiency on an industrial scale.

Abstract: Process for continuous preparation of homo- and copolyoxymethylenes with stable end groups in a homogeneous phase, in which in a tubular reactor with static mixing elements cyclic formaldehyde oligomers are polymerized in the presence of protonic acids as initiators in amounts of 0.005 to 500 ppm in a polymerization zone, in which the residence time of the reaction components in this zone is 0.1 to 10 min and in which the initiator is deactivated immediately after polymerization, there being a fluid transition between the polymerization and deactivator zones which is determined solely by the addition of deactivator, and in which, besides deactivation, stabilization of the chain ends is carried out in the presence of residual monomers, with the volatile constituents being removed from the reaction mixture in a subsequent vent unit. Stabilization is carried out in the presence of alkaline substances, either at temperatures of 150.degree. C. to 250.degree. C.

Abstract: High molecular weight polyamides are prepared by(a) polymerizing monomers selected from the group consisting of aminonitriles of the formula IH.sub.2 N--(CH.sub.2).sub.m --CN Iand mixtures of diamines of the formula IIH.sub.2 N--(CH.sub.2).sub.n --NH.sub.2 IIwith dinitriles of the formula IIINC--(CH.sub.2).sub.p --CN IIIwhere m, n and p are integers from two to twelve, in a molar diamine/dinitrile ratio of from 0.98:1 to 1.02:1 to give a prepolymer capable of being granulated,(b) granulating the prepolymer obtained under (a) and(c) subjecting the granules obtained under (b) to solid-phase postcondensation at from 5.degree. to 100.degree. C. below the melting point of the prepolymer in the presence of an inert gas which contains at least 50% by volume of superheated steam to give a high molecular weight polyamide having a relative viscosity of from 2.3 to 5.

Abstract: A process for producing a resin for the chromatographic extraction of metal ions is provided, the process involving:treating an acidic bidentate organic phosphonate metal complexing agent with an alcohol or ketone solvent containing an aqueous alkaline solution, thereby forming the corresponding salt of the phosphonate compound;mixing the bidentate organic phosphonate salt with an absorbent resin in an alcohol or ketone solvent containing an aqueous alkaline solution, thereby absorbing the phosphonate salt in the resin;washing the resin containing bidentate complexing agent with an aqueous alcohol or ketone solution; anddrying the washed resin, wherein the process provides improved chromatographic extraction of metal ions.

Abstract: The invention provides a process for preparing a polyester comprising a liquid phase polycondensation step in which a dicarboxylic acid including terephthalic acid or its ester derivative and a diol including ethylene glycol or its ester derivative are subjected to polycondensation reaction in liquid phase and molten state under heating in the presence of a polycondensation catalyst to produce a polyester (a) having an intrinsic viscosity, as measured in o-chlorophenol, of 0.7 to 1.5 dl/g; a hot water treatment step in which the polyester (a) is contacted with hot water of 60.degree. to 130.degree. C. for 30 minutes to 10 hours; a drying step in which the polyester after the hot water treatment step is dried at a temperature of 110.degree. to 150.degree. C. for 30 minutes to 6 hours; and a heat treatment step in which the polyester after the drying treatment step is heated at a temperature of 160.degree. to 200.degree. C.

Abstract: A process and an apparatus for the continuous crystallization of plastic granules, particularly amorphous plastic granules, in which the granules are introduced into a container and form a granule bed, which is moved downwards by the action of gravity. A hot gas is passed as a primary gas in a countercurrent manner through the granule bed. The granules are kept moving by a stirrer. There is also a gas supply for a secondary gas, which introduces the secondary gas at high speed at several points distributed over the cross-section of the container into the upper area of the granule bed.

Abstract: A method for cleaning elastomeric articles comprising contacting the elastomeric article with at least one supercritical fluid under conditions and for a time sufficient to remove the phthalates and/or polynuclear aromatic hydrocarbons (PAHs) contained therein. Elastomeric articles having a reduced phthalte and/or PAH content prepared by the above method are also claimed. Such elastomeric articles having reduced phthalate contents can be utilized as gaskets, valves, seats, flaps or plugs in metered dose delivery devices such as aerosols for demanding medicinal and pharmaceutical uses.

Abstract: Plasticizers are homogeneously incorporated into finely divided solid polyamides by mechanically agitating a mixture of plasticizers and polyamides at temperatures of at least 80.degree. C. while the polyamide remains in the finely divided solid phase.

Abstract: The efficiency of a redistribution catalyst during polycarbonate redistribution is improved by employing an extruder screw design that provides a melt seal between the extruder throat and the vacuum port. A melt seal exists when the free volume within the extruder is sufficiently filled with molten resin so as to prevent the passage of gases between sections of the extruder.

Abstract: A system for the solid phase polymerization of polymers wherein cold amorphous polymer is introduced to a crystallizer and heated to crystallize the polymer, the crystallized polymer is discharged to a reactor to achieve polymerization of the polymer, and the hot polymer product of the reactor is discharged to a fluid bed cooler for cooling of the polymerized product. The fluid bed cooler includes an inlet for the hot polymer and an inlet for the cooling gas, and the cooled polymer and the heated gas are discharged from the cooler after contact of the gas with the polymer. The cooler includes a bed portion through which the polymer moves while in contact with the cooling gas, and an upper chamber which collects the heated gas.

Abstract: A composition comprising a copolyestercarbonate derived from a dihydric phenol, a carbonate precursor, and an aliphatic alpha omega dicarboxylic acid or ester precursor wherein the dicarboxylic acid or ester precursor has from 10 to about 20 carbon atoms, inclusive, and is present in the copolyestercarbonate in quantities of from about 2 to 30 mole percent of the dihydric phenol.

Abstract: There is a need for polymers which are utilized in automotive interiors which offer increased heat and ultraviolet light resistance. It is particularly critical for polymers which are utilized in making skin compounds for automotive instrument and door panels to display excellent heat and ultraviolet light resistance. This invention discloses a rubbery polymer which can be blended with polyvinyl chloride to make leathery compositions having good heat and ultraviolet light resistance, said rubbery polymer being comprised of repeat units which are comprised of (a) butyl acrylate, or optionally a mixture of butyl acrylate and 2-ethylhexyl acrylate containing up to about 40% 2-ethylhexyl acrylate, (b) at least one member selected from the group consisting of methyl methacrylate, ethyl methacrylate, methyl acrylate, and ethyl acrylate, (c) acrylonitrile, (d) styrene, (e) a half ester maleate soap, and (f) a crosslinking agent.

Abstract: A sealing material is prepared by furnishing a liquid composition comprising a polydiene or polyolefin polyol, a polyisocyanate compound, a foam stabilizer, and a blowing agent, uniformly dispersing an inert gas in the liquid composition by mechanical agitation to form a bubbled composition, shaping the bubbled composition into a sheet shape, and heat curing the bubbled shape at a temperature below the decomposition temperature of the blowing agent. The sealing material is lightweight and has a high blowing magnification. On use, the sealing material is disposed in a cavity of an automotive pillar or similar member and heated for foaming to fill the cavity with the foamed product.

Abstract: A method for the production of an absorbent resin, which method comprises mixing 100 parts by weight of (A) a hydrated gel of absorbent resin which is resulted from aqueous solution polymerization having a polymerization ratio in the range of from 60 to 99%, an average particle diameter in the range of from 0.1 to 200 mm, a water content in the range of from 30 to 90% by weight, and a temperature in the range of from 40.degree. to 110.degree. C., with from 1 to 50 parts by weight of (B) a substantially dry fine absorbent resin powder having an average particle diameter smaller than the average particle diameter assumed by said hydrated gel of absorbent resin (A) while in a dried state, then raising the polymerization ratio of said hydrated gel of absorbent resin (A) to a level higher than the polymerization ratio of said hydrated gel when being mixed.

Abstract: A medical implant made of polymeric material having an increased oxidation resistance is formed by a method including the steps of placing a resin powder in a sealed container. A substantial portion of the oxygen is removed from the sealed container by either a vacuum, an oxygen absorbent or by flushing with inert gas. The container is then repressurized with a gas such as nitrogen, argon, helium or neon so that long term storage may be possible. On use, the resin is transferred to a forming device which both melts and forms the resin in an oxygen reduced atmosphere to produce a polymeric raw material such as a rod or bar stock. The medical implant is then formed from this raw material annealed and sealed in an air-tight package in an oxygen reduced atmosphere. The implant is then radiation sterilized and thereafter annealed in the package for a predetermined time and temperature sufficient to form cross-links between any free radicals in neighboring polymeric chains.

Abstract: This invention includes a process for preparing a solid state polymerized poly(ethylene naphthalate)or PEN polymer comprising: (1) preparing a molten PEN polymer with an intrinsic viscosity of from about 0.25 dl/g to about 0.55 dl/g, (2) dispersing an inert gas into the molten PEN polymer to form a foamed PEN polymer with a void fraction of from about 0.10 to about 0.50, (3) forming the foamed PEN polymer into granules, (4) devolatilizing the granular PEN polymer at a temperature of from about 80.degree. C. to about 140.degree. C., (5) crystallizing the devolatilized PEN polymer at a temperature of from about 150.degree. C. to about 260.degree. C., and (6) solid state polymerizing the crystallized PEN polymer at a temperature of from about 235.degree. C. to about 265.degree. C. to form a solid state polymerized PEN product.

Abstract: A process for producing polyethylene terephthalate comprises the following steps 1 and 2:1 a moisture conditioning step of contacting a polyethylene terephthalate having an intrinsic viscosity of from 0.5 to 1.5 dl/g, a density of at least 1.37 g/cm.sup.3 and a cyclic trimer content of at most 5,000 ppm, with water to bring the water content of the polyethylene terephthalate to from 1,000 to 5,000 ppm, and2 a heat aging step of holding the moisture-conditioned polyethylene terephthalate obtained by the above moisture conditioning step, in a state where its water content is maintained at a level of at least 1,000 ppm.

Abstract: In a process for producing a polycarbonate by subjecting a dihydroxy compound and a diester of carbonic acid to melt polycondensation through transesterification, after a polycarbonate prepolymer is prepared in the first-stage reaction, polycondensation is conducted as the second-stage reaction at a residence time in the range of from 15 to less than 60 min or through the use of at least one paddle-type self-cleaning twin-screw extruder.This process enables a colorless, transparent polycarbonate having a high molecular weight to be produced at a high efficiency on an industrial scale.

Abstract: Methods of performing an assay for biomolecules and solid supports for use in such assays are disclosed. An activated polymeric material is used as a solid support for binding biomolecules. In a preferred form, the support is made of a generally hydrophobic, nonporous polymer which has been activated by treatment with solvents or by mechanical means to enhance the binding characteristics of the support. The support can be made of a copolymer, such as a copolymer of polystyrene and polybutadiene. Detection of bound biomolecules is preferably performed by means of staining reactions and gray level scanning. Emulsifying agents, such as detergents, can be applied to the surface of the support to substantially inhibit additional materials from being bound to the support.

Abstract: The present invention is directed to a method for treating cross-linked (cured) filled or untilled unsaturated polyester for deriving an alcohol recycle reactant useful in the synthesis of alcohol-formed derivative products. The first step of the method is the attrition of the cured unsaturated polyester to form particulates thereof. In the next step of the process, at least a fraction of any filler or fiberglass in the cured unsaturated polyester is separated to form a cured unsaturated polyester regrind. The next step is the subjecting of the cured unsaturated polyester regrind to agitated, uncatalyzed or catalyzed glycolysis in the presence of excess glycol and, optionally, a transesterification catalyst under agitation at elevated transesterification temperature. The final step of the process is the recovery of the recycle alcohol reactant for use in the synthesis of alcohol-formed derivative products.

Abstract: Polyester prepolymer granules with open-ended cavities provide greatly improved solid state polymerization rates by improving reaction by-product diffusion characteristics.